[c-nsp] TCP throughput /WAN delay simulation with back to back routers

[Kaegler, Mike]

If you have a linux machine laying around (a default ubuntu install will
do...), drop it on the same subnet as either one of the two PCs. (only one
ethernet card needed)

Do:
iptables -A OUTPUT -p icmp --icmp-type redirect -j DROP
tc qdisc add dev eth0 root netem delay 45msec
echo -n 1 > /proc/sys/net/ipv4/ip_forward

On the PC on the same subnet, set the default gateway to be the IP of the
linux machine. Done. You can change the delay with `tc qdisc change dev eth0
root netem delay <whatever>`

This technically only induces delay in one direction (you could do it
bidirectionally by sending it from the router to the linux box) but the net
net won't affect your LFN testing.
-porkchop


On 8/19/09 3:17 PM, "Thilak T" <thilak.t at gmail.com> wrote:

> Hello Folks ,
> 
> I am trying to test TCP throughput with different variables. I want to
> simulate a delay of aprox 45msec between two test PCs connected two
> bat to back routers . How do we introduce an artificial delay where in
> the actual delay is on 2-3 msec.Using cisco routers.?
> 
> Thilak
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
> 

-- 
Michael Kaegler, TESSCO Technologies: Engineering, 410 229 1295
Your wireless success, nothing less. http://www.tessco.com/